基于四重氢键作用的相变保温聚氨酯

以一种新型含四重氢键脲基嘧啶酮单元（2-脲-4[1H]-嘧啶酮,UPy）的二元醇为扩链剂,扩链异氰酸酯基封端的1,6-己二异氰酸酯（HDI）与聚乙二醇（PEG）合成的聚氨酯预聚物,成功合成了含四重氢键单元的相变保温聚氨酯。通过DSC、XRD、黏度测试及拉伸力学性能测试对聚氨酯进行了性能分析。结果表明：该聚氨酯具有较好的...     

高交联苯乙烯—二乙烯苯共聚物的孔结构研究

我们以甲苯或甲苯-正庚烷为致孔剂合成了一系列高交联的大孔苯乙烯-二乙烯苯(St-DVB)共聚物,本文报道这些共聚物的孔结构、孔结构稳定性及其与合成条件的关系。     

新型烷氧基修饰的手性SalenMn（Ⅲ）固载催化剂的合成及其在非功能化烯烃不对称环氧化反应中的应用

合成了一系列以有机聚合物-无机杂化材料聚（苯乙烯-苯乙烯基膦酸）-磷酸氢锆（ZPS-PVPA）为载体,烷氧基为连接基团的新型固载手性Salen Mn（III）催化剂,并运用FT-IR,UV-vis,XPS,SEM,TG,元素分析等手段对其进行了表征.以m-CPBA为氧化剂,茚和α-甲基苯乙烯为底物,考察了催化剂对非功能...     

含双键大孔径苯乙烯—二乙烯基苯微球的合成与表征

含双键大孔径苯乙烯－二乙烯基苯微球的合成与表征袁青阚成友刘伟良孔祥正＊（山东大学化学系济南２５０１００）关键词苯乙烯－二乙烯基苯共聚树脂，悬浮聚合，树脂微球，复合致孔剂，孔结构１９９７－０７－０３收稿，１９９８－０１－１２修回国家教委留学服务中心回国...     

丝素蛋白-聚氨酯水凝胶的制备和性能

以异佛尔酮二异氰酸酯（IPDI）、聚乙二醇（PEG）、聚氧化丙烯二醇（PPG）等为主要原料,合成了一系列—NCO封端的水性聚氨酯（PU）预聚体,与自制的丝素蛋白（SF）水溶液混合进行交联反应,制备出丝素蛋白-聚氨酯（SF-PU）水凝胶。研究了SF-PU水凝胶的合成工艺,对SF-PU水凝胶进行了红外和电镜表征及性能测试,...     

吸附型“人工肝”辅助材料的合成及其性能研究Ⅰ大孔吸附树脂对芳香氨基酸的吸附性能

合成了苯乙烯型大孔吸附剂（MacroreticularAdsorbentMA）测定其孔结构参数，考察吸附剂对芳香氨基酸的吸附性能。实验结果表明，MA－2型吸附剂对芳香氨基酸具有特异性吸附，而对支链氨基酸吸附为非特异性吸附，其血液相容性良好。     

聚氨酯-丙烯酸酯杂化乳液结构与性能的影响

以聚四氢呋喃醚二醇（PTMG）、异氟尔酮二异氰酸酯（IPDI）、亲水单体二羟甲基丙酸（DMPA）,乙二胺为主要原料,制备了稳定的水性聚氨酯乳液.然后以苯乙烯（St）、丙烯酸丁酯（BA）为单体,过硫酸钾为引发剂,在不外加乳化剂的条件下,运用物理共混、化学复合和化学共聚三种方法对该水性聚氨酯乳液进行改性研究.用FTIR技术对聚氨酯-丙烯酸酯杂化乳液的结构进行了对比与表征;通过粘度测定、粒度分析、力学性能和耐水性能测试、DSC分析,研究了不同改性方法对乳液及其胶膜性能的影响.结果表明,化学共聚的改性方法对原水性聚氨酯的耐水性的改良效果最好,能够得到稳定且综合性能较优的聚氨酯-丙烯酸酯杂化乳液.     

Heck反应合成1,2-二芳基乙烯类衍生物的新方法

以1,3-二乙烯基-1,1,3,3-四甲基二硅氧烷（DVS）为烯源与溴代芳烃通过Heck反应一步法合成了1,2-二苯乙烯（V-bisPh）及1,2-二苯并环丁烯基乙烯（V-bisBCB）。 优化了反应条件：DMF/H2O为溶剂,温度120 ℃,溴化物（R-Br）与烯源DVS的投料摩尔比为5∶1,反应48 h,1,2-二苯并环丁烯基乙烯产率为45.1%,1,2-二苯乙烯产率为48.6%。     

含UPy侧链聚氨酯的合成与性能

以二苯基甲烷二异氰酸酯（MDI）和聚四氢呋喃醚二醇（PTMG）合成预聚体,用2-甲基-2-UPy（2-脲-4[H]-嘧啶酮）基-1,3-丙二醇为扩链剂制备了一系列侧链含UPy的聚氨酯。利用FT-IR、1 H-NMR、DMA和力学性能测试等手段对该聚氨酯的结构和性能进行了表征。结果表明：该聚氨酯的力学性能与不含UPy基团的聚氨酯相比有较大的提升;UPy的四重氢键效应形成的物理交联网络结构,使该聚氨酯的玻璃化转变温度随UPy含量的增加向高温方向移动,损耗角正切（tanδ）峰减弱;在宽频的频率场中,随着UPy含量增加,tanδ峰向低频移动,峰强减弱,储能模量增大。     

NMP与ROP相结合制备PCL-b-PSt共聚物及其性能研究

以4-羟基-2,2,6,6-四甲基哌啶氮氧自由基（HTEMPO）为引发剂,通过ε-己内酯（ε-CL）的开环聚合,合成末端基为氮氧自由基的聚己内酯（PCL-T）。在其调控下,进行过氧化苯甲酰（BPO）引发苯乙烯（St）的自由基聚合,合成结构规整的聚己内酯-b-聚苯乙烯（PCL-b-PSt）共聚物。用氢核磁共振（1H-NM...     

α-Amino acid derived enaminones and their application in the synthesis of N-protected methyl 5-substituted-4-hydroxypyrrole-3-carboxylates and other heterocycles

A new and simple synthesis of novel N-protected methyl 5-substituted-4-hydroxypyrrole-3-carboxylates, which exist in equilibrium with their 4-oxo tautomers, has been developed in two steps starting from N-protected α-amino acids. The key intermediates are enaminones, which can also be isolated, characterized, and used for the construction of other functionalized heterocycles, before they spontaneously decompose to pyrrole products. 4-Hydroxypyrroles are prone to partial aerial oxidation but can be efficiently alkylated or reduced to stable polysubstituted pyrrolidine derivatives.     

Specific intramolecular aromatic CH insertion of diazosulfonamides

The chemoselectivity in the intramolecular CH insertion of various diazosulfonamides has been experimentally studied. The results reveal that the aliphatic 1,4-, 1,5-, or 1,6-C(sp³)?H insertions of diazosulfonamides are not accessible, while the aromatic 1,5-C(sp²)?H insertion can be realized specifically by adjusting the diazo-adjacent group. In addition, the general chemoselectivities in the intramolecular CH insertions of diazosulfonyl compounds are summarized. Generally, diazosulfones undergo both aromatic 1,5-C(sp²)?H and aliphatic 1,5- and 1,6-C(sp³)?H insertions, while diazosulfonates undergo aliphatic 1,5- and 1,6-C(sp³)?H insertions. However, diazosulfonamides only undergo aromatic 1,5-C(sp²)?H insertion.     

N-Heterocyclic carbene-palladacyclic complexes: synthesis,characterization and their applications in the C-N coupling and α-arylation of ketones using aryl chlorides

N-Heterocyclic carbene-palladacyclic complexes 3 were successfully achieved in a one-pot procedure under mild conditions. The structure of 3a was unambiguously confirmed by X-ray single crystal diffraction and it was an active catalyst in the Buchwald-Hartwig amination and α-arylation of ketones even at very low catalyst loadings (0.01?mol%).     

Iodine-mediated oxidative Pictet-Spengler reaction using terminal alkyne as the 2-oxoaldehyde surrogate for the synthesis of 1-aroyl-β-carbolines and fused-nitrogen heterocycles

An efficient iodine-mediated oxidative Pictet-Spengler reaction in dimethyl sulphoxide (DMSO) using terminal alkynes as the 2-oxoaldehyde surrogate for the synthesis of aryl (9H-pyrido[3,4-b]indol-1-yl)methanones is described. The scope of the protocol includes the total synthesis of Fascaplysin, Eudistomins Y₁ and Y₂. The methodology is extended for preparing pyrrolo[1,2-a]-quinoxaline and indolo[1,5-a]quinoxaline derivatives. The utility of 1-aroyl-β-carbolines was demonstrated by performing palladium-catalyzed β-carboline directed ortho-C(sp2)-H functionalization of the phenyl ring with thiomethyl (SMe) group using DMSO as source and for accessing 4-aryl-canthin-6-ones.     

Facile synthesis of bicyclic 1-arylpyrazol-5-ones

In this Letter, we described a facile method for constructing fused bicyclic 1-arylpyrazol-5-one ring system. We employed various methylene-containing carboxylic acids as the substrates and proved that the pyrazolone ring closure requires activated methylene group in intermediate II. Accordingly, a series of structurally diversified, fused bicyclic 1-arylpyrazol-5-ones was prepared in moderate to high yields using the requisite substrates.     

Synthesis of pyrrolo[1,2-a]pyrazines and pyrazino[1,2-a]indoles by Curtius reaction in Morita-Baylis-Hillman derivatives

Synthesis of substituted pyrrolo[1,2-a]pyrazines and pyrazino[1,2-a]indoles from the Morita-Baylis-Hillman derivatives of acrylates via saponification followed by Curtius reaction is described.     

Cu0-catalysed 1,3-dipolar cycloadditions of α-amino acid derived N,N-cyclic azomethine imines to ynones

A series of 20 CuAIAC reactions between eight 4-acylamino substituted pyrazolidine-3-one-1-azomethine imines and four terminal ynones were performed using Cu⁰ as catalyst. The corresponding fluorescent cycloadducts were obtained in very high yields upon simple workup. Thus, Cu-metal turned out to be a better catalyst than Cu^I in terms of yield and ease of isolation. Availability of azomethine imines, mild reaction conditions, and simple workup enable a “click” access to libraries of densely substituted 2,3-dihydro-1H,5H-pyrazolo[1,2-a]pyrazol-1-ones. Reactivity of differently substituted dipoles was evaluated experimentally and by quantum chemical methods (DFT).     

Synthesis and antioxidative/anti-inflammatory activity of novel fullerene–polyamine conjugates

(E)-4-(Fullerenopyrrolidin-1-yl)-3-methylbut-2-enoic acid and its corresponding succinimidyl ester, readily obtained through Prato-type modification of C₆₀, were used for the selective N-acylation of polyamines. The thus obtained conjugates were evaluated for their antioxidative and anti-inflammatory activity and their cytotoxicity was determined. Members of this family of compounds showed interesting anti-lipid peroxidation, anti-lipoxygenase and anti-inflammatory activity and comparable cytocompatibility to spermidine.     

Copper-catalyzed multicomponent reactions of 2-iodoanilines,benzylamines, and elemental sulfur toward 2-arylbenzothiazoles

A relatively cheap copper salt-catalyzed, three-component approach providing 2-arylbenzothiazoles in good to excellent yields from readily available 2-iodoanilines, benzylamines, and sulfur powder is reported. This methodology allows preparation of various classes of 2-arylbenzothiazoles and provides a general, reliable approach.